Effects of Yohimbine on Human Sympathetic Nervous System Function*
| Autor: | Richard C. Veith, Grant N. Ko, Enrique C. Villacres, M. Michele Murburg |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Adult
Male medicine.medical_specialty Sympathetic nervous system Sympathetic Nervous System Epinephrine Endocrinology Diabetes and Metabolism Clinical Biochemistry Administration Oral Biochemistry Norepinephrine Endocrinology Internal medicine Heart rate medicine Humans Dose-Response Relationship Drug Chemistry Biochemistry (medical) Yohimbine Venous Plasma Autonomic nervous system medicine.anatomical_structure Catecholamine medicine.drug |
| Zdroj: | The Journal of Clinical Endocrinology & Metabolism. 73:861-865 |
| ISSN: | 1945-7197 0021-972X |
| DOI: | 10.1210/jcem-73-4-861 |
| Popis: | The alpha 2-adrenergic receptor antagonist yohimbine is often used as a neuroendocrine probe in human studies, in which it is assumed to increase plasma norepinephrine (NE) by increasing sympathetic outflow. In this study we have tested that assumption by using a radioisotope dilution technique to measure norepinephrine (NE) kinetics in arterialized plasma after administration of oral yohimbine (20 or 40 mg) or placebo to normal young men. In agreement with previous studies, we found that yohimbine causes dose-dependent increases in blood pressure, heart rate, and plasma NE. We further found that the increase in plasma NE is, in fact, due to an increase in the rate of appearance of NE into plasma and not to reduced NE clearance from plasma. In addition, we found that yohimbine causes a dose-dependent increase in plasma epinephrine, which had not been found in studies measuring catecholamines in venous plasma. We conclude that yohimbine increases plasma NE levels by increasing the rate of NE release from sympathetic nerves, and probably increases epinephrine release from the adrenals. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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